Sound-producing instrument



Aug. l0 1926. 1,595,343

F. B. LITTLE SOUND PRODUCING INSTRUMENT Filed May 4. 1925 Patented Aug. 10, 1926.

UNITED STATES PATENT OFFICE.

FREDERICK B. LITTLE, OF CHICAGO, ILLINOIS, ASBIGNOR TO J. C. DEAGAN, INC., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SOUND-PBODUCING INSTRUMENT.

Application tiled lay 4, 1925. Serial No. 27,768.

My invention relates to sound producing instruments, and has for its object the provision of an improved sound damper in conjunction with the sound producing member.

In accordance with my invention the sound producing member serves as a back stop to limit the damping movement of the sound damper, this sound damper being preferably the armature of an electromagnet, whereby the sounds produced by the sound producing member are dampened. This sound producing member may be in the form of a bar such as is commonly employed in making chimes. The armature is attracted upon ene-rgization of the magnet to permit the bar to sound, when struck.

In the preferred embodiment of the invention the armature or damper floats, the means for floating the armature being desirabl a spring structure which is supporte by the winding element of the magnet. The damping action of the amature is desirably regulated by adjusting the position of the winding element toward or from the bar whereby the pressure of the spring structure exerted upon the bar through the intermediation of the magnet armature is regulable.

, The invention will be more fully explained in connection with the accompanying drawing, in which Fig. 1 is a. diagrammatic illustration of two sounding bars, electromagnetic mechanism for sounding the same, and the preferred form of electromagnetic mechanism for damping the sounds produced by the bars; Fig. 2 is a vertical j sectional View of the damping mechanism as it is preferably constructed, taken on line 2-2 of Fig. 3, the bottom end of the bar being shown in conjunction therewith; and Fig. 3 is a sectional view on line 3-3 of Fig. 2.

The two sounding bars 1 and 2 may be of' a group constituting a set of chimes or other musical instrument. Each of these bars is suitably mounted in au upright position, preferably depending from a support 3 permitting it to freely vibrate, when struck by a hammer, such as the hammer 4, which is normally retracted by a spring 5 and which is applied to the bar by means of an electromagnet 6. The circuit of this ma lnet is governed by a key 7, this key servlng,

when depressed, to include a suitable source of current 8 in circuit with the magnet. A floatmg .sound damper is provided below each uprlght sounding bar, this sound damper belng desirably inclusive of an armature 9 that is faced with felt or other sound deadenmg material 10 that directly engages the bottom end of the bar. A spring structure, preferably inclusive of four upright colled springs 11, normally serves to apply each sound damper to the bar having the same, the sound damper floating upon these springs, whereby its extended and uniform engagement with the bottom face of the correspondlng sounding bar is assured. These coiled springs are desirably contained with- 1n vupright sockets 12 that are formed in an annular extension 13 of the core 14, the central portion of this core being surrounded by the energizing magnet coil 15 which is lncluded in parallel with the particular sounding magnet 6 pertaining to the soundmg bar to which the damping magnet also pertains. Thus, whenever a sounding magnet 6 of a. bar is energized to apply the. hammer 4 to the bar to produce sound, the sound damper is withdrawn from engagement with the bar to permit the bar to sound, this adjustment of the damper being maintained as long as the key is in circuit closing position. When the key is released the armature 9 is retracted or withdrawn lfrom the winding element of the magnet, to an extent limited by the corresptnding sounding bar which thus serves as a back stop for the armature. The winding element of each damping magnet is desirably immediately below and is coaxial with the sounding bar pertaining thereto, the armature of the magnet being interposed between the winding element and the bar. The core portion of the winding element of the magnet is desirably carried upon four upright screws 16 which are threaded into the annular core extension 13. The lower ends of these screws are conical and enter the holes 17 provided in the circular plates 18 which, themselves, are screwed upon the foundation board 19. By turning the screws 16 the core ortion of the winding element is raised or owered to adjust the tension of the springs 11 to regulate the pressure thereof upon the corresponding sounding bar these springs.

The armature is desirably circular and is 1 mounted coaxial with the corresponding winding by means of the bolt 20 which is coaxial with the winding and the armature, the armature sliding snugly upon this bolt. If desired, the armature may be provided with a cylindrical depending projection 21 which closely surrounds the annular extension 13 of the Winding core 14 further to assure maintenance of the coaxial relation of the armature and the magnet winding.

Changes may be made Without departing from my invention.

Having thus delcribed my invention, I claim:

Thepcombination with an u right sounding bar; of an electro-magnet below the bar and provided with an armature located between the winding element of the magnet and the bar; and a spring structure upon which said armature fioats and which presses the amature toward the bar to the extent permitted by the bar, when the magnet is deenergized, to dampen the sounds produced by the bar.

In Witness whereof I hereunto subscribe my name.

FREDERICK B. LITTLE. 

